ASTM A213 T11 Alloy Steel Seamless Boiler & Superheater Tubes
Overview & Performance Characteristics
Designed for critical thermal application environments, our ASTM A213 Grade T11 (ASME SA213 T11) seamless low-alloy steel tubes represent the industry standard for superheaters, reheaters, and high-pressure steam systems. Formulated with a balanced nominal composition of 1.25% Chromium and 0.5% Molybdenum (1.25Cr-0.5Mo-Si), T11 tubing delivers superior creep-rupture strength, high thermal conductivity, and exceptional resistance to steam-side oxidation and hydrogen attack at operating temperatures up to 565°C (1050°F).
Manufactured via precision hot-finished or cold-drawn seamless processes, each tube undergoes normalized and tempered (N+T) heat treatment to guarantee uniform microstructural stability and optimal ductility under thermal cycling.
Technical Specifications & Dimension Ranges
Our ASTM A213 T11 tubing is supplied in standard and customized dimensional profiles engineered to meet strict ASME Section I and Section VIII boiler build codes:
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Outer Diameter (OD): 1/8" to 5" (3.2 mm to 127 mm)
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Wall Thickness (WT): 0.015" to 0.500" (0.4 mm to 12.7 mm) in Minimum Wall (MW) or Average Wall (AW) options
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Length: Single Random (5–7 m), Double Random (10–12 m), or Custom Cut-to-Length
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Manufacturing Craft: Cold Drawn (smooth finish, high tolerance) or Hot Finished (heavy wall applications)
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End Finishes: Plain End (PE), Beveled End (BE) for welding, or Threaded
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Surface Protection: Anti-corrosion light oil coating, black varnish, or pickling/passivation
Chemical Composition (Weight %)
The precise elemental chemistry of ASTM A213 T11 ensures structural integrity and high-temperature corrosion performance:
| Element |
Specification Limits (%) |
| Carbon (C) |
0.05 – 0.15 |
| Manganese (Mn) |
0.30 – 0.60 |
| Phosphorus (P) |
≤ 0.025 |
| Sulfur (S) |
≤ 0.025 |
| Silicon (Si) |
0.50 – 1.00 |
| Chromium (Cr) |
1.00 – 1.50 |
| Molybdenum (Mo) |
0.44 – 0.65 |
Mechanical Properties
| Property |
Standard Requirement |
| Tensile Strength, min. |
415 MPa (60 ksi) |
| Yield Strength, min. |
205 MPa (30 ksi) |
| Elongation in 2 in. (50 mm), min. |
30% |
| Hardness, max. |
163 HBW / 85 HRB |
| Max Service Temp (Creep-Limit) |
565°C (1050°F) |
Quality Control & Testing Methods
Every length of ASTM A213 T11 superheater tubing undergoes rigorous non-destructive and destructive testing in compliance with ASTM A1016/A1016M standards before dispatch:
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Hydrostatic Testing: 100% factory hydrostatic pressure tested to verify pressure boundary integrity without leakage.
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Non-Destructive Electric Testing (NDT): Ultrasonic Testing (UT) or Eddy Current Testing (ET) performed across full tube length to detect surface/subsurface flaws.
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Mechanical Mechanical Tests:
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Flattening Test: Ensures weldability and material ductility without cracking.
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Flaring / Expanding Test: Confirms tube end expandability during header insertion.
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Hardness Testing: Verified via Brinell or Rockwell scales to ensure compliance with heat-treatment boundaries.
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Dimensional & Surface Inspection: Full-length laser micrometer measurement to verify OD and WT tolerances.
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Material Traceability: 100% Positive Material Identification (PMI) verified with EN 10204 3.1 Mill Test Certificates provided with every shipment.
Primary Applications
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Fossil Fuel Thermal Power Plant Superheaters & Reheaters
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Waste-to-Energy and Biomass Fired Boilers
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Petrochemical Fired Heaters and Heat Exchanger Bundles
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Marine High-Pressure Boiler Tubing Systems
